Paul Maritz, a 14-year veteran of Microsoft who managed platform strategy before retiring in 2000, is putting his efforts behind open source software projects these days.

Maritz, who grew up in southern Africa, advised the development of a new open source platform at the Grameen Technology Center in Seattle. That project, called Mifos, was created to help microfinance institutions around the world manage tens of thousands of accounts without having to buy complex, proprietary software.

Maritz recently joined the board of the Grameen Foundation, the organization connected to the bank that pioneered microfinance, or extending credit and other financial services to the world's poorest people. Volunteers are invited to contribute to the Mifos project, which is written in Java and set for release in November.